CN106405064B - A kind of appraisal procedure of 40 years old or more women bone turnover rate - Google Patents

Abstract

The present invention provides a method for evaluating the bone turnover rate of women over 40 years old, which comprises the following steps: (a) measuring the content of osteocalcin in serum to obtain a measured value C _s , in units of ng/mL; (b) taking the local age Statistically obtain the first critical value D ₁ and the second critical value D ₂ for the serum osteocalcin content of women aged 30-50, in ng/mL, where 1≤D ₁ ≤8, 12≤D ₂ ≤28; (c) Compare the measured value C _s with the first critical value D ₁ and the second critical value D ₂ : when C _s < D ₁ , it is judged as low bone turnover rate; when D ₁ ≤ C _s < D ₂ , It is judged as normal bone turnover rate; when C _s ≥ D ₂ , it is judged as high bone turnover rate.

Description

A method for evaluating bone turnover rate in women over 40 years old

technical field

The invention relates to a method for evaluating bone turnover rate.

Background technique

Osteocalcin is a protein composed of 49 amino acids. It is derived from bone tissue, synthesized by osteoblasts and secreted into bone. It is the main component of non-collagenous protein in bone tissue. Its function is to regulate and maintain bone calcium, and it can basically reflect recent osteoblast activity and bone turnover. Case.

Intact osteocalcin (amino acids 1-49) is unstable in peripheral blood, and the amino acid chain between carboxy-terminal 43 and 44 is easily hydrolyzed by proteases. The large fragment (amino acids 1-43) after cleavage contains 43 amino acids, which is called the N-terminal molecular fragment of osteocalcin or osteocalcin-N-terminal peptide (N-MID), and the osteocalcin-N-terminal peptide is in Relatively stable in peripheral blood. Therefore, in order to accurately determine the content of osteocalcin in serum, it is necessary to detect the content of the whole segment of osteocalcin (amino acid 1-49) and osteocalcin-N-terminal peptide (amino acid 1-43) in serum at the same time. It can better reflect the recent bone turnover, so that it can further diagnose and observe the curative effect of bone metabolic diseases.

At present, there are only a few companies in the market that can produce in vitro diagnostic reagents that simultaneously detect the full segment of osteocalcin and osteocalcin-N-terminal peptide in serum, such as Roche Diagnostics Co., Ltd., Jiaxing Xingjian Biotechnology Co., Ltd., Guangzhou Fei Kang Biotechnology Co., Ltd., etc. However, accurate detection of serum osteocalcin content is only the first step in evaluating the bone turnover rate, and the critical value for evaluating the bone turnover rate is the key.

In medical analysis, the critical value is usually based on the measured value of a group of not less than 120 healthy people (considering factors such as region, gender, age, etc.), and for most analytes, the lower limit is 2.5%. , with 97.5% as the upper limit, usually the determined range of 2.5% to 97.5% is the critical value. For one-sided indicators, the 5th percentile or 95th percentile can be determined as the critical value. Roche Diagnostics Co., Ltd. also follows the usual practice in the statistics of osteocalcin cut-off value. For women, before menopause (> 20 years old), the measured value of 108 premenopausal healthy women is 5% to 95% (ie 11-43ng/mL ) is the critical value; after menopause, the measured value of 102 postmenopausal healthy women is 5%-95% (that is, 15-46ng/mL). However, in women at the beginning of menopause, there is an accelerated period of bone loss, mainly due to the decrease of estrogen level, which leads to the increase of osteoclast activity and bone resorption, which is manifested by the gradual increase of osteocalcin level. In women 20 years after menopause, the level of osteocalcin remains at a relatively stable high level. Therefore, the bone health population of women should not include the postmenopausal population (women in this age group already have a large bone loss), but should be based on the premenopausal female population. The design defect of Roche osteocalcin on the cut-off value makes it difficult to be applied clinically, and the consistency with other clinical diagnoses (such as bone density detection) is poor. Therefore, the existing bone turnover rate evaluation methods are difficult to be effectively applied clinically.

Contents of the invention

In view of the above problems, the purpose of the present invention is to provide a more accurate method for evaluating the bone turnover rate of women over 40 years old, so as to solve the problems in the prior art.

The present invention provides a method for evaluating the bone turnover rate of women over 40 years old, which comprises the following steps:

(a) Determination of the content of osteocalcin in serum to obtain the measured value C _s , in ng/mL;

(b) Set the first critical value D ₁ and the second critical value D ₂ in ng/mL, where 1≤D ₁ ≤8, 12≤D ₂ ≤28;

(c) Compare the measured value C _s with the first critical value D ₁ and the second critical value D ₂ : when C _s < D ₁ , it is judged as low bone turnover rate; when D ₁ ≤ C _s < D ₂ , It is judged as normal bone turnover rate; when C _s ≥ D ₂ , it is judged as high bone turnover rate.

Preferably, in step (a), the content of osteocalcin in serum is determined by an in vitro diagnostic reagent method.

Preferably, an in vitro diagnostic reagent method is used to measure the content of molecular fragments and whole fragments of osteocalcin in the N-terminal of serum, and the in vitro diagnostic reagent method is enzyme-linked immunoassay, immunoturbidimetric method or chemiluminescence method.

Preferably, in step (b), the first critical value D ₁ and the second critical value D ₂ are obtained through statistical analysis of the osteocalcin content in the serum of local women aged 34-44.

Preferably, in step (b), 2≤D ₁ ≤5, 15≤D ₂ ≤19, unit ng/mL.

Compared with the prior art, the bone turnover rate evaluation method of the present invention obtains the first critical value D ₁ and the second critical value D ₂ through statistics of the osteocalcin content in the serum of women aged 30-50 in the local area , comparing and judging the measured value of osteocalcin with the first critical value and the second critical value, and the value ranges of D ₁ and D ₂ are: 1≤D ₁ ≤8, 12≤D ₂ ≤28. Compared with the existing cut-off value of postmenopausal women as the bone health population (there is already a large bone loss), the statistical object of this cut-off value basically excludes the population of postmenopausal women, so it can accurately express the state of bone health. Osteocalcin assessment results are basically consistent with other detection methods such as bone density testing. The assessment method of osteocalcin can further carry out more effective and accurate diagnosis and curative effect observation on clinical bone metabolic diseases.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, not all of them. Based on the implementation manners in the present invention, all other implementation manners obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

The present invention provides a method for evaluating the bone turnover rate of women over 40 years old, which comprises the following steps:

(a) Determination of the content of osteocalcin-N-terminal peptide in serum to obtain the measured value C _s , in ng/mL;

(b) Statistically obtain the first critical value D ₁ and the second critical value D ₂ based on the serum osteocalcin content of local women aged 30-50, in ng/mL, where 1≤D ₁ ≤8, 12 ≤D ₂ ≤28;

(c) Compare the measured value C _s with the first critical value D ₁ and the second critical value D ₂ : when C _s < D ₁ , it is judged as low bone turnover rate; when D ₁ ≤ C _s < D ₂ , It is judged as normal bone turnover rate; when C _s ≥ D ₂ , it is judged as high bone turnover rate.

In step (a), the content of molecular fragments (amino acids 1-43) and the whole segment of osteocalcin (amino acids 1-49) in the N-terminal of osteocalcin in serum is determined by using an in vitro diagnostic reagent method. The method for measuring the content C _s of osteocalcin in serum is not limited, and may be enzyme-linked immunoassay, immunoturbidimetric method, chemiluminescence method and the like. In this embodiment, the method for measuring the content _Cs of osteocalcin in serum is the osteocalcin-N-terminal peptide assay kit (enzyme-linked immunosorbent assay), which can simultaneously measure the whole segment of osteocalcin and the N-terminal molecular fragment bone Calcium. Specifically, the kit adopts the "double-antibody sandwich" technology, that is, by adding biotin-labeled osteocalcin antibody and horseradish peroxidase (HRP)-labeled osteocalcin antibody mixture, incubate to form a "biotin antibody-bone Calcein-HRP-labeled antibody" double-antibody sandwich structure, then add HRP matrix solution, incubate, and measure the absorbance. The test value C _s of the osteocalcin concentration was obtained by the absorbance-osteocalcin concentration curve.

In step (b), the first critical value D ₁ and the second critical value D ₂ are different due to geography, race, gender and age. Preferably, the first critical value D ₁ and the second critical value D ₂ are obtained through statistics based on the serum osteocalcin content of local women aged 34-44. Preferably, 2≤D ₁ ≤5, 15≤D ₂ ≤19.

In step (c), the bone turnover rate is evaluated by comparing the measured value C _s with the _first critical value D1 and the _second critical value D2. Generally speaking, when a woman's age exceeds 40 years old, the probability of suffering from osteoporosis increases. When it is judged that the bone turnover rate is high, it is suitable for anti-resorptive drug therapy; when it is judged that the bone turnover rate is low, it is not suitable to use anti-bone resorptive drug therapy, but drugs that increase bone anabolic metabolism can be used.

This evaluation method can be used to evaluate bone metabolism status, osteoporosis diagnosis and classification, prediction of fracture risk, evaluation of anti-osteoporosis treatment efficacy, differential diagnosis of metabolic bone diseases, evaluation of fracture healing, detection of tumor bone metastasis, etc.

The method for evaluating the bone turnover rate of women over 40 years old according to the present invention will be described below in conjunction with specific examples:

Example 1

Establishing the critical value: Taking 131 healthy women aged 30-50 in a certain area of China as the statistical object, the content of osteocalcin-N-terminal peptide in serum was determined by the osteocalcin-N-terminal peptide assay kit (enzyme-linked immunoassay) To establish the cut-off value of serum osteocalcin for women over 40 years old in this area, take D ₁ =P ₅ , D ₂ =P ₉₅ , the results are shown in Table 1. Note: P ₅ and P ₉₅ are percentile points.

Table 1

In 33 cases of women over 40 years old in this area, the content of osteocalcin-N-terminal peptide in serum was measured with osteocalcin-N-terminal peptide assay kit (enzyme-linked immunoassay), compared with bone densitometry (DXA) measurement The bone density, the results are shown in Table 2.

Table 2

After statistical analysis, the bone turnover rate evaluation results are shown in Table 3.

table 3

Remarks: In the evaluation results of osteocalcin-N-terminal peptide: Positive (I) indicates low bone turnover rate; Negative indicates normal bone turnover rate; Positive (II) indicates high bone turnover rate. Positive rate=[Positive (I)+Positive (II)]/Number of divided cases*100%.

It can be seen from Table 3 that the evaluation results of osteocalcin-N-terminal peptide of each female in Table 2 are consistent with the test results of bone density, which further verifies that the evaluation method is more accurate. The positive rate of osteocalcin-N-terminal peptide gradually increased with the increase of bone loss.

Further, among the 12 cases of osteoporosis patients in Table 3, 8 cases were high turnover rate osteoporosis, suitable for anti-bone resorption therapy (using bone resorption inhibitors such as bisphosphonates); 1 case was low bone turnover rate, 3 cases had normal bone turnover rate osteoporosis and were not suitable for anti-resorptive therapy. There were 12 patients with osteopenia, including 0 cases with low conversion rate and 5 cases with normal conversion rate, which were not suitable for anti-resorptive prophylaxis; and 7 cases with high conversion rate, suitable for anti-resorptive prophylaxis.

Example 2

Establishing the critical value: Taking 128 healthy women aged 34-44 in a certain area of China as statistical objects, the content of osteocalcin-N-telopeptide in serum was determined by using an osteocalcin-N-telopeptide assay kit (enzyme-linked immunoassay) , to establish the critical value of serum osteocalcin for women over 40 years old in this region, taking D ₁ =P ₅ , D ₂ =P ₉₅ , and the results are shown in Table 4. Note: P ₅ and P ₉₅ are percentile points.

Table 4

In 36 cases of women over 40 years old in this area, the content of osteocalcin-N-terminal peptide in serum was measured with osteocalcin-N-terminal peptide assay kit (enzyme-linked immunoassay), compared with bone densitometer (DXA) measurement The bone density, the results are shown in Table 5.

table 5

After statistical analysis, the bone turnover rate evaluation results are shown in Table 6.

Table 6

Remarks: In the evaluation results of osteocalcin-N-terminal peptide: Positive (I) indicates low bone turnover rate; Negative indicates normal bone turnover rate; Positive (II) indicates high bone turnover rate. Positive rate=[Positive (I)+Positive (II)]/Number of divided cases*100%.

It can be seen from Table 6 that the evaluation results of osteocalcin-N-terminal peptide of each female in Table 5 are consistent with the test results of bone density, which further verifies that the evaluation method is more accurate. The positive rate of osteocalcin-N-terminal peptide gradually increased with the increase of bone loss.

Further, among the 13 cases of osteoporosis patients in Table 6, 8 cases were high turnover rate osteoporosis, suitable for anti-bone resorption therapy (using bone resorption inhibitors such as bisphosphonates); 2 cases were low bone turnover rate, 3 cases had normal bone turnover rate osteoporosis and were not suitable for anti-resorptive therapy. There were 14 patients with osteopenia, including 1 case with low conversion rate and 6 cases with normal conversion rate, who were not suitable for anti-resorptive prophylaxis; and 7 patients with high conversion rate, who were suitable for anti-resorptive prophylaxis.

Compared with the prior art, the bone turnover rate evaluation method of the present invention sets the first critical value D ₁ and the second critical value D ₂ , and compares the measured value of osteocalcin-N-telopeptide with the first critical value , the second critical value for comparison and judgment, the value range of D ₁ and D ₂ is: 1≤D ₁ ≤8, 12≤D ₂ ≤28, the value range is small, so it can be more accurately judged bone Calcium-N-terminal peptide content, the evaluation result of osteocalcin is basically consistent with other detection methods such as bone density test. The assessment method of osteocalcin can further carry out more effective and accurate diagnosis and curative effect observation on clinical bone metabolic diseases.

The descriptions of the above embodiments are only used to help understand the method and core idea of the present invention. It should be pointed out that for those skilled in the art, without departing from the principle of the present invention, some improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention will not be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (5)

1. A method for assessing bone turnover rate of women over 40 years old, comprising the steps of: (a) Determination of the content of osteocalcin in serum to obtain the measured value C _s , in ng/mL; (b) Statistically obtain the first critical value D ₁ and the second critical value D ₂ based on the serum osteocalcin content of local women aged 30-50, in ng/mL, where 1≤D ₁ ≤8, 12 ≤D ₂ ≤28; (c) Compare the measured value C _s with the first critical value D ₁ and the second critical value D ₂ : when C _s < D ₁ , it is judged as low bone turnover rate; when D ₁ ≤ C _s < D ₂ , It is judged as normal bone turnover rate; when C _s ≥ D ₂ , it is judged as high bone turnover rate. 2. A method for evaluating the bone turnover rate of women over 40 years old as claimed in claim 1, characterized in that, in step (a), adopt an in vitro diagnostic reagent method to measure the content of osteocalcin in serum. 3. a method for assessing the bone turnover rate of women over 40 years old as claimed in claim 2, characterized in that, adopt the in vitro diagnostic reagent method to measure the molecular fragment and the osteocalcin in the N-terminal of osteocalcin in serum The in vitro diagnostic reagent method is enzyme-linked immunoassay, immunoturbidimetric method or chemiluminescence method. 4. A method for assessing the bone turnover rate of women over 40 years old as claimed in claim 1, characterized in that, in step (b), the osteocalcin content in the serum of women aged 34-44 in the local area is statistically obtained The first critical value D ₁ and the second critical value D ₂ . 5 . A method for assessing bone turnover rate of women over 40 years old according to claim 1 , wherein in step (b), 2≤D ₁ ≤5, 15≤D ₂ ≤19, unit ng/mL.